[native_assets_cli] BuildOutput extension: addDataAssetDirectories

pkgs/native_assets_builder/test_data/simple_data_asset/hook/build.dart

@@ -1,34 +1,11 @@
 // Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-import 'dart:io';
 
-import 'package:native_assets_cli/data_assets.dart';
+import 'package:native_assets_cli/native_assets_cli.dart';
 
 void main(List<String> args) async {
   await build(args, (input, output) async {
-    final assetDirectory = Directory.fromUri(
-      input.packageRoot.resolve('assets/'),
-    );
-    // If assets are added, rerun hook.
-    output.addDependency(assetDirectory.uri);
-
-    await for (final dataAsset in assetDirectory.list()) {
-      if (dataAsset is! File) {
-        continue;
-      }
-
-      // The file path relative to the package root, with forward slashes.
-      final name = dataAsset.uri
-          .toFilePath(windows: false)
-          .substring(input.packageRoot.toFilePath(windows: false).length);
-
-      output.assets.data.add(
-        DataAsset(package: input.packageName, name: name, file: dataAsset.uri),
-      );
-      // TODO(https://github.com/dart-lang/native/issues/1208): Report
-      // dependency on asset.
-      output.addDependency(dataAsset.uri);
-    }
+    await output.addDataAssetDirectories(['assets'], input: input);
   });
 }

pkgs/native_assets_cli/CHANGELOG.md

@@ -2,6 +2,7 @@
 
 - Added validation that all URLs in the `Input` and `Output` of hooks are
   absolute.
+- Added `addDataAssetDirectories` extension method on `BuildOutputBuilder`.
 
 ## 0.11.0
 

pkgs/native_assets_cli/example/build/download_asset/hook/build.dart

@@ -32,12 +32,19 @@ void main(List<String> args) async {
         outputDirectory,
       );
       final fileHash = await hashAsset(file);
-      final expectedHash =
-          assetHashes[createTargetName(
-            targetOS.name,
-            targetArchitecture.name,
-            iOSSdk?.type,
-          )];
+      final targetName = createTargetName(
+        targetOS.name,
+        targetArchitecture.name,
+        iOSSdk?.type,
+      );
+
+      // Create a lookup where the keys have their file extension removed.
+      final normalizedHashes = {
+        for (final entry in assetHashes.entries)
+          entry.key.substring(0, entry.key.lastIndexOf('.')): entry.value,
+      };
+
+      final expectedHash = normalizedHashes[targetName];
       if (fileHash != expectedHash) {
         throw Exception(
           'File $file was not downloaded correctly. '

pkgs/native_assets_cli/lib/native_assets_cli.dart

@@ -12,6 +12,7 @@ export 'src/api/link.dart' show link;
 export 'src/api/linker.dart' show Linker;
 export 'src/config.dart'
     show
+        AddDataAssetsDirectoryExtension,
         BuildConfig,
         BuildConfigBuilder,
         BuildInput,

pkgs/native_assets_cli/lib/src/config.dart

@@ -8,10 +8,10 @@ import 'dart:io';
 import 'package:crypto/crypto.dart' show sha256;
 import 'package:pub_semver/pub_semver.dart';
 
+import '../data_assets.dart';
 import 'api/deprecation_messages.dart';
 import 'encoded_asset.dart';
 import 'hook/syntax.g.dart' as syntax;
-import 'metadata.dart';
 import 'utils/datetime.dart';
 import 'utils/json.dart';
 
@@ -404,6 +404,78 @@ class BuildOutputBuilder extends HookOutputBuilder {
       syntax.BuildOutput.fromJson(super._syntax.json);
 }
 
+extension AddDataAssetsDirectoryExtension on BuildOutputBuilder {
+  /// Extension on [BuildOutput] to handle data asset directories and files.
+  ///
+  /// This extension provides a convenient way for build hooks to add
+  /// [DataAsset] dependencies from one or more directories or individual files.
+  ///
+  /// If any specified path does not exist, a [FileSystemException] is thrown.
+  /// Any error during the directory listing is caught and rethrown with
+  /// additional context.
+  ///
+  /// When recursive is set to true, the method will also add all subdirectories
+  /// and their files as dependencies.
+  Future<void> addDataAssetDirectories(
+    List<String> paths, {
+    required BuildInput input,
+    bool recursive = false,
+  }) async {
+    final packageName = input.packageName;
+    final packageRoot = input.packageRoot;
+    final rootPath = packageRoot.toFilePath(windows: false);
+
+    String assetName(Uri assetUri) =>
+        assetUri.toFilePath(windows: false).substring(rootPath.length);
+
+    for (final path in paths) {
+      final resolvedUri = packageRoot.resolve('$packageName/$path');
+      final directory = Directory.fromUri(resolvedUri);
+      final file = File.fromUri(resolvedUri);
+
+      if (await directory.exists()) {
+        try {
+          await for (final entity in directory.list(
+            recursive: recursive,
+            followLinks: false,
+          )) {
+            if (entity is File) {
+              assets.data.add(
+                DataAsset(
+                  package: packageName,
+                  name: assetName(entity.uri),
+                  file: entity.uri,
+                ),
+              );
+              addDependency(entity.uri);
+            }
+          }
+        } on FileSystemException catch (e) {
+          throw FileSystemException(
+            'Error reading directory "$path": ${e.message}',
+            directory.path,
+            e.osError,
+          );
+        }
+      } else if (await file.exists()) {
+        assets.data.add(
+          DataAsset(
+            package: packageName,
+            name: assetName(file.uri),
+            file: file.uri,
+          ),
+        );
+        addDependency(file.uri);
+      } else {
+        throw FileSystemException(
+          'Path does not exist',
+          resolvedUri.toFilePath(windows: Platform.isWindows),
+        );
+      }
+    }
+  }
+}
+
 extension type EncodedAssetBuildOutputBuilder._(BuildOutputBuilder _output) {
   /// Adds [EncodedAsset]s produced by this build.
   ///

pkgs/native_assets_cli/test/data_assets/validation_test.dart

@@ -108,4 +108,106 @@ void main() {
     );
     expect(errors, contains(contains('More than one')));
   });
+
+  test('addDataAssetDirectories processes multiple directories', () async {
+    final input = makeDataBuildInput();
+    final outputBuilder = BuildOutputBuilder();
+
+    final assetsDir1Uri = packageRootUri.resolve('assets1');
+    final assetsDir1 = Directory.fromUri(assetsDir1Uri);
+    await assetsDir1.create(recursive: true);
+
+    final assetsDir2Uri = packageRootUri.resolve('assets2');
+    final assetsDir2 = Directory.fromUri(assetsDir2Uri);
+    await assetsDir2.create(recursive: true);
+
+    // Create a file in assets1.
+    final file1Uri = assetsDir1.uri.resolve('file1.txt');
+    final file1 = File.fromUri(file1Uri);
+    await file1.writeAsString('Hello World');
+
+    // Create a file in assets2.
+    final file2Uri = assetsDir2.uri.resolve('file2.txt');
+    final file2 = File.fromUri(file2Uri);
+    await file2.writeAsString('Hello Dart');
+
+    final output = BuildOutput(outputBuilder.json);
+    await outputBuilder.addDataAssetDirectories([
+      'assets1',
+      'assets2',
+    ], input: input);
+
+    // Check that the files in both directories were added as dependencies.
+    expect(output.dependencies, contains(file1Uri));
+    expect(output.dependencies, contains(file2Uri));
+  });
+
+  test('addDataAssetDirectories processes one file', () async {
+    final input = makeDataBuildInput();
+    final outputBuilder = BuildOutputBuilder();
+
+    final assetsDirUri = packageRootUri.resolve('single_assets');
+    final assetsDir = Directory.fromUri(assetsDirUri);
+    await assetsDir.create(recursive: true);
+
+    // Create a file in the single_assets directory.
+    final fileUri = assetsDir.uri.resolve('single_file.txt');
+    final file = File.fromUri(fileUri);
+    await file.writeAsString('Test content');
+
+    final output = BuildOutput(outputBuilder.json);
+    await outputBuilder.addDataAssetDirectories([
+      'single_assets/single_file.txt',
+    ], input: input);
+
+    // Check that the file in the directory was added as a dependency.
+    expect(output.dependencies, contains(fileUri));
+  });
+
+  test('addDataAssetDirectories processes nested directories', () async {
+    final input = makeDataBuildInput();
+    final outputBuilder = BuildOutputBuilder();
+
+    // Create top-level assets directory.
+    final assetsDirUri = packageRootUri.resolve('assets3');
+    final assetsDir = Directory.fromUri(assetsDirUri);
+    await assetsDir.create(recursive: true);
+
+    // Create nested subdirectory.
+    final nestedDirUri = assetsDir.uri.resolve('subdir');
+    final nestedDir = Directory.fromUri(nestedDirUri);
+    await nestedDir.create(recursive: true);
+
+    final nestedDir2Uri = nestedDir.uri.resolve('subdir2');
+    final nestedDir2 = Directory.fromUri(nestedDir2Uri);
+    await nestedDir2.create(recursive: true);
+
+    // Create a file in the top-level assets directory.
+    final fileTopUri = assetsDir.uri.resolve('top_file.txt');
+    final fileTop = File.fromUri(fileTopUri);
+    await fileTop.writeAsString('Top level file');
+
+    // Create a file in the nested subdirectory.
+    final nestedFileUri = nestedDir.uri.resolve('nested_file.txt');
+    final nestedFile = File.fromUri(nestedFileUri);
+    await nestedFile.writeAsString('Nested file');
+
+    // Create a file in the nested subdirectory.
+    final nestedFile2Uri = nestedDir2.uri.resolve('nested_file2.txt');
+    final nestedFile2 = File.fromUri(nestedFile2Uri);
+    await nestedFile2.writeAsString('Nested file 2');
+
+    final output = BuildOutput(outputBuilder.json);
+    await outputBuilder.addDataAssetDirectories(
+      ['assets3'],
+      input: input,
+      recursive: true,
+    );
+
+    // Verify that the top-level directory, nested directory, and both files are
+    // added.
+    expect(output.dependencies, contains(fileTopUri));
+    expect(output.dependencies, contains(nestedFileUri));
+    expect(output.dependencies, contains(nestedFile2Uri));
+  });
 }